LED and BUD QUALITY

[greyfader]

When it comes to led and veg, honestly im no expert. Ive just seen what happens when i crank the light up and early on it caused some issues. 1200 ppfd for veg sounds very intense, did they start out that way or did you work your way up to that?

well, you made me go back and check and this is from the grow;

"the first 12 days i used a 1.4 ec nutrient solution and about 700 umols of light then brought the ec up to 1.8 and the light to 1000 umols. i'm giving them 6 hours on and 6 hours off around the clock but alternating so only one is on at a time but the room is never dark."

so only the last week of the veg period was at 1200 ppfd. the first 12 days at 700 ppfd for 12 hours and then 1000 for 2 days before going to 1200.

700 umols for 12 hrs is 30.24 mols, 1000 is 43.2 mols and 1200 is 51.84.

so, i guess i did ramp them up.

here is one plant at transplant from 2.5 quart passive ppk type containers to 6 gal active, and then at 2 weeks and 3 weeks at the flip.

editing to add that in the 2 week middle pic i didn't have the reflectix cover on and you can see the roots emerging around the halo.

editing again to say that this plant had only been under 5000k white light it's entire life up through this point and until the end of the 3rd week of flower.

 

[Katrak]

hhmmm

 

[Hiddenjems]

there has to be more to this than light and co2 as i vegged my last plants at 1200 ppfd for 12 hours a day for a DLI of about 52 with no supplemented co2.

i also vegged at ec1.8 or 900 ppm. i saw no displays. here's one of the plants at the flip after 3 weeks veg under these conditions.

View attachment 18985277

People forget how much Dli goes up with lights on 18-24hrs for veg. It doesn’t take much ppfd if you light 20 hrs.

 

[maryjaneismyfre]

I've had issues with yellow plants and such post transplant plenty, in coco perlite, in sealed rooms under LEDs and working out the dynamic has been fun. But once you do...

The LEDs make less heat or infrared, even when you have red bars in like I do. But the light is clean and bright and even, even if ppfd is not high..I find they have higher food requirements, but the conditions that drive drinking and hence feeding are less, lower leaf temps and less transpiration. So the nutrient uptake less but demands higher. I find then that any sodium still left in the coir can and will cause trouble as the fresh coir is busy loading up on all the other cations and none left for the transplant, and also I find runoff EC's lower than feed EC showing me plants hungry and they look it.

So what I have found works well, is drive them harder from transplant, higher light, higher temperatures and lower RH than optimal VPD for the initial period after transplant. One can get VPD in perfect range for veg sure but im talking about the first take off of the plant, drive it. Feed higher EC as transpiration lower so feed demands relative to water demands are higher, and elevate K and Ca to overcome any sodium left in the media affecting their uptake. I find a calcium and potassium nitrate foliar feed completely in 2 days greens up yellow plants and during the entire time they look like they hate me the roots are amazing and banging out the bottom of the pot white and strong so its not watering nor food recipe, it was just feed strength relative to water given based on water demands being less but feed demands being higher.

But when off the bat higher EC feed given with elevated K and Ca then there is no problem, along with higher temps and lower RH initially..

If you read the documentation from Athena, on LED growing, it says basically first feed after transplant feed at EC 4.0 range in sealed CO2 rooms..thats pretty much it. I don't need to feed that high but feeding high like that initially avoids the issue of the plants looking yellow and underfed prior to establishing themselves.

In the greenhouses I can transplant clones into 40 degree summer heat as I have no choice, and the next day they are lying on the ground and look like death, but im watering them daily already from the second day and by day four they are exploding into life, green as anything and roots are coming out the bottom of the bags already..putting them into such harsh environments but them loving it, in a kushy climate controlled indoor room LED's Co2 dehumidifuers, humidifiers, aircons, perfect VPD, and on same food recipe they will hate me and look like death in 5 days of the perfect environment, go figure...they need a little bit of a push, and a strong feed initially for best results. If ones plants are not infected with shit. If they are, its a whole other chasing your tail endlessly trying to dial shit and work out problems...

 

[Crooked8]

I've had issues with yellow plants and such post transplant plenty, in coco perlite, in sealed rooms under LEDs and working out the dynamic has been fun. But once you do...

The LEDs make less heat or infrared, even when you have red bars in like I do. But the light is clean and bright and even, even if ppfd is not high..I find they have higher food requirements, but the conditions that drive drinking and hence feeding are less, lower leaf temps and less transpiration. So the nutrient uptake less but demands higher. I find then that any sodium still left in the coir can and will cause trouble as the fresh coir is busy loading up on all the other cations and none left for the transplant, and also I find runoff EC's lower than feed EC showing me plants hungry and they look it.

So what I have found works well, is drive them harder from transplant, higher light, higher temperatures and lower RH than optimal VPD for the initial period after transplant. One can get VPD in perfect range for veg sure but im talking about the first take off of the plant, drive it. Feed higher EC as transpiration lower so feed demands relative to water demands are higher, and elevate K and Ca to overcome any sodium left in the media affecting their uptake. I find a calcium and potassium nitrate foliar feed completely in 2 days greens up yellow plants and during the entire time they look like they hate me the roots are amazing and banging out the bottom of the pot white and strong so its not watering nor food recipe, it was just feed strength relative to water given based on water demands being less but feed demands being higher.

But when off the bat higher EC feed given with elevated K and Ca then there is no problem, along with higher temps and lower RH initially..

If you read the documentation from Athena, on LED growing, it says basically first feed after transplant feed at EC 4.0 range in sealed CO2 rooms..thats pretty much it. I don't need to feed that high but feeding high like that initially avoids the issue of the plants looking yellow and underfed prior to establishing themselves.

In the greenhouses I can transplant clones into 40 degree summer heat as I have no choice, and the next day they are lying on the ground and look like death, but im watering them daily already from the second day and by day four they are exploding into life, green as anything and roots are coming out the bottom of the bags already..putting them into such harsh environments but them loving it, in a kushy climate controlled indoor room LED's Co2 dehumidifuers, humidifiers, aircons, perfect VPD, and on same food recipe they will hate me and look like death in 5 days of the perfect environment, go figure...they need a little bit of a push, and a strong feed initially for best results. If ones plants are not infected with shit. If they are, its a whole other chasing your tail endlessly trying to dial shit and work out problems...

You just inspired me to up my feed a touch at transplant to veg.

 

[woolybear]

I finished a run with a 2x4 VIPARSPECTRA XS2500 and a 3x3 KS3000. Both did extremely well.

Extremely chunky, resinous buds.

I think I may buy another XS2500, $169 on amazon currently after coupon. I think I paid around $300 for the KS3000.

 

[CharlesU Farley]

I finished a run with a 2x4 VIPARSPECTRA XS2500 and a 3x3 KS3000. Both did extremely well.

Extremely chunky, resinous buds.

I think I may buy another XS2500, $169 on amazon currently after coupon. I think I paid around $300 for the KS3000.

I run an XS4000 in my 2x5 clone/seedling closet and paid 300 bucks for it 2 years ago. Outstanding light, unlike Spider Farmer, they still use Meanwell drivers... even if they are probably knock offs.

 

[goingrey]

I run an XS4000 in my 2x5 clone/seedling closet and paid 300 bucks for it 2 years ago. Outstanding light, unlike Spider Farmer, they still use Meanwhile drivers... even if they are probably knock offs.

View attachment 18985878

If it's a Meanwhile instead of a Mean Well it's a knockoff for sure.

 

[CharlesU Farley]

If it's a Meanwhile instead of a Mean Well it's a knockoff for sure.

Didn't even have time to edit that one, gotta love voice dictation!

 

[woolybear]

I found the XS2500 on sale for $152.99 on eBay, so all in about $30 cheaper than my first purchase. Nice!

Interesting that the brand has been around for a couple of years

 

[CharlesU Farley]

If it's a Meanwhile instead of a Mean Well it's a knockoff for sure.

Reminds me of the Rolax watch people try to sell me in Times Square.

 

[goingrey]

Reminds me of the Rolax watch people try to sell me in Times Square.

Brought a homie an "Adihash" t-shirt with a serrated edge trefoil as a souvenir from a trip once.

 

[CocoNut 420]

Did someone say Rolex?

 

[Prawn Connery]

there has to be more to this than light and co2 as i vegged my last plants at 1200 ppfd for 12 hours a day for a DLI of about 52 with no supplemented co2.

i also vegged at ec1.8 or 900 ppm. i saw no displays. here's one of the plants at the flip after 3 weeks veg under these conditions.

View attachment 18985277

1200 umol/s for 12 hours is the same as 800 umol/s for 18 hours so DLI is more indicative of what plants can handle.

Also, I'm not saying this to be funny, but there are some signs of light stress in the above image if you look at the leaf margins. The plants are otherwise very healthy, so I'd suggest you are near the limit.

A lot has to do with plant health and chlorophyl saturation. If you crank up the light too soon, before the plant has acclimatised, then it will suffer and photo-oxidation will make things worse. I made the mistake the other day of putting some new clones directly under about 600 PPFD for 20 hours and the tops started to go chloratic until I dimmed the lights a little. After a week they were back under about 600-700 PPFD and looking very happy.

I also believe it is strain dependent. Thinner leaves absorb less light, and I have found sativas can always take more light than indicas. There is a trend for growers to mass defoliate, and that also doesn't help because light just keeps bouncing around until it is photosynthesised or absorbed as heat. That's why you see a lot of pink stems (anthocyanins) on mass defol grows, because there aren't enough fan leaves to absorb the light that hits the stems and stresses the plant.

 

[greyfader]

1200 umol/s for 12 hours is the same as 800 umol/s for 18 hours so DLI is more indicative of what plants can handle.

Also, I'm not saying this to be funny, but there are some signs of light stress in the above image if you look at the leaf margins. The plants are otherwise very healthy, so I'd suggest you are near the limit.

A lot has to do with plant health and chlorophyl saturation. If you crank up the light too soon, before the plant has acclimatised, then it will suffer and photo-oxidation will make things worse. I made the mistake the other day of putting some new clones directly under about 600 PPFD for 20 hours and the tops started to go chloratic until I dimmed the lights a little. After a week they were back under about 600-700 PPFD and looking very happy.

I also believe it is strain dependent. Thinner leaves absorb less light, and I have found sativas can always take more light than indicas. There is a trend for growers to mass defoliate, and that also doesn't help because light just keeps bouncing around until it is photosynthesised or absorbed as heat. That's why you see a lot of pink stems (anthocyanins) on mass defol grows, because there aren't enough fan leaves to absorb the light that hits the stems and stresses the plant.

i vegged 12 hours per 24 by alternating the 2 plants 6 on and 6 off. they are in the same room so no induction.

definitely some light stress as i'm always pushing them hard. this isn't a spa for plants, it's the gulag!

just joking, of course.

my next grow i will be more conservative on the light intensity. probably limit veg to 1000 umols for 12 hours which is 43.2 mols per day.

i found quite a few growers in oregon using a 12 hour veg to balance temperature and rh in multiple interconnected rooms. they would keep a small light on to prevent flowering.

as you said, it's about DLI.

 

[Hammerhead]

Getting high quality using a cheap LED can happen. I have 1 no brand China 850w(250$) It grows plants as well as any 1000$ LED, even better than one of the most widely used LED lights. Results should always be the driving factor where your $ goes.

 

[CharlesU Farley]

Also, I'm not saying this to be funny, but there are some signs of light stress in the above image if you look at the leaf margins. The plants are otherwise very healthy, so I'd suggest you are near the limit.

Other than overt bleaching, I'm not sure I can even identify light stress. Take a look at this bud shot from yesterday and have at it. Other than a bit of burning on the leaf tips, that are from variations in fertilizer concentration among 20+plants, everything looks normal to me:

That bud was approximately 3-4 inches away, in the center of a new version of SF 2000, about a half to 2/3 of the way through flowering.

I wonder what the PAR measurement would be there?

I don't freak out or get concerned about individual leaves or margins showing stress, it's the _buds_ I'm concerned about.

A lot has to do with plant health and chlorophyl saturation. If you crank up the light too soon, before the plant has acclimatised, then it will suffer and photo-oxidation will make things worse. I made the mistake the other day of putting some new clones directly under about 600 PPFD for 20 hours and the tops started to go chloratic until I dimmed the lights a little. After a week they were back under about 600-700 PPFD and looking very happy.

I used to treat clones just like everybody else, angle cut, dip in hormone, reduced/low lighting from t5s, exceedingly gentle, etc. Then about 10 or 15 years ago I decided to start treating clones just like I do SouthEast Lights seedlings. No more babying, gentle treatment, etc. just treat it like any other little seedling, full and complete light, just 3 to 4 ft above the clones rather than two to three inches when plants are in full flower.

I lose over 50% of them but the ones that survive I know will be tough, strong, resilient plants.

I also believe it is strain dependent. Thinner leaves absorb less light, and I have found sativas can always take more light than indicas. There is a trend for growers to mass defoliate, and that also doesn't help because light just keeps bouncing around until it is photosynthesised or absorbed as heat. That's why you see a lot of pink stems (anthocyanins) on mass defol grows, because there aren't enough fan leaves to absorb the light that hits the stems and stresses the plant.

I am positive the reason I don't get leaf burn like others is because they've been generationally exposed to high intensity light, regardless of the source, for _many_ decades.

Maybe next we can discuss how LED lighting will _never_ be able to penetrate the canopy with its light and reach _deep_ down into the lower branches.

 

[CocoNut 420]

I don't hurry to increase intensity, i get my plants to about this point before I really start increasing intensity even then its still done slowly.

It's now 14 days ± since I installed the led, starting at 430w 18/20k lux im now at 565w 47k lux @15" away.
Most of that change was this week so I'm going to hold off now for a bit and see how they respond?

Eta...April 4th, the day I potted them for flowering.

 

[Deleted user 90433]

LED or any other under powered bulbs (low w CFLs) will not mature the trichomes enough.
They will grow killer plants, very healthy, but dont do much for in flowering.
there's a reason why your HPS buds are great, can you guess what it is ? ))

Without offending I have to disagree,I'm running a hlg350 far red and a hlg 650r full spectrum and I grow nuggets that nice that most people smoke to much of it and green out after 2 or 3 billy's,my missus only smokes before bed for a better sleep and she can't have any more than 2 puffs,I'm not sure how you see that trichomes don't mature under led lights,I'd be interested in more info on the matter if you can elaborate for me.

 

[Deleted user 90433]

Show me, show me a pic like i showed u under LED... full trichome heads across the entire flower structure leaves etc... sorry, you wont find one.
LED are great dont get me wrong bro, they are not fitted to flower anything, not stuff that need the highest intensity ever, science says to up the ppdf when your flowering, but science also told u not to go over 1000 ppfd as its not necessary, when you dont go above and beyond (in light intensity) you will get poor resulst, no matter the light source, and LED prove that, just look, leave the science papers in favor of your eyes for a sec.

this smaller nugget is still about 3 weeks from finishing and it was under full spectrum led and I've only got the dimmer set between 600-700 ppfd,anything over that severely burns the plants